This document presents a control theory view of human performance and its implications for managing performance. It argues that current views of human performance are inadequate and misleading. It proposes that people are "living control systems" that act to control their perceptions of aspects in the world. Performance is influenced by goals, perceptions, discrepancies between goals and perceptions, actions, and other conditions. For managing complex performance where results are indirect, managers should focus on goals, perceptions, distinguishing between behavior and performance, and enabling effective interventions, rather than trying to control behavior. The key is helping performers frame interventions that work through the situation's structure to achieve desired results.